Effect of sulphur crosslinking on the stability and transition of triple helical DNA
S Srivastava1, V D Gupta, S Singh
1Division of Biopolymers, Central Drug Research Institute, Lucknow, India.
Abstract:
In continuation to our work on order-order and order-disorder transition in triple stranded DNA when it is bounded to netropsin, we report in this communication the stabilizing/destabilizing effect of disulphide linkage on the phase dynamics of the triplex using the amended Zimm-Bragg theory. It is observed that in contrast to the sequential triplex-->duplex -->single strand melting of the uncrosslinked triplex, crosslinking causes the triplex state to melt directly to the single stranded state, with no apparent intermediary of a duplex state. Since there is no overall difference in the enthalpy of crosslinked and uncrosslinked triplexes, the transition is entropy driven.
Related Concept Videos
Single-Strand DNA Binding Proteins
Protein Folding
DNA Topoisomerases
Types and Mechanism of action
Topoisomerases are divided into two main types. Type I...
Stability of Conjugated Dienes
A comparison of the enthalpies of hydrogenation of dienes reveals that conjugated dienes release less heat on hydrogenation, rendering them more stable than their nonconjugated analogs.
Fixing Double-strand Breaks
DNA as a Genetic Template

